What are astigmatism contact lenses and how do I choose them?
How to choose contact lenses for astigmatism?
Astigmatism is also known as misalignment and pediatric astigmatism, which can coexist with nearsightedness or farsightedness. The main cause of astigmatism is the irregularity of the corneal curvature because the cornea is not round, but an elliptical hemisphere, and if the vertical curvature is different from the lateral curvature, it will cause a refractive error and distort the light entering the eye, resulting in blurred images.
In the face of vision problems, many people choose to wear contact lenses in addition to glasses. Still, it is important to note that once astigmatism affects your daily life, it is essential to pay more attention to the choice of contact lenses.
If you are astigmatism but choose a contact lens without astigmatism, or if you choose a lens with an incorrect amount of astigmatism or an incorrect axis, your vision may be blurred or even damaged. It is recommended that you evaluate your own needs and situation, or consult a medical professional before deciding whether to purchase toric contact lenses.
Toric contact lens prescription conversion
If you decide to wear toric contact lenses, you should be aware that there is a difference between the prescription of glasses and the prescription of toric contact lenses, and you should not look at the prescription of glasses alone.
Astigmatism contact lens prescription conversion formula.
Nearsightedness + (Astigmatism ÷ 2) = Astigmatism contact lens prescription (take the minimum value)
For example, if you currently wear glasses with a prescription of 500 degrees and your astigmatism is 50 degrees, you can apply the above conversion formula to get “500 + (50 ÷ 2) = 525”, and then you can choose a 525-degree contact lens.
Note: The above formula is applicable to astigmatism below 100 degrees. If the astigmatism is above 100 degrees, it is best to consult a professional doctor for a custom-made astigmatic occult eye.
Astigmatism labeling interpretation
In addition to the degree of astigmatism, it is advisable to seek professional optometrists to understand your own vision status, such as whether you have astigmatism or presbyopia, and then select the right toric contact lenses for you based on the data results obtained.
But when you go to the shelf, looking at a bunch of English words on the package, is there something you don’t quite understand? The following is a list of common labels and their numerical meanings on astigmatism contact lens packages.
SPH (or labeled as Sphere): Spherical prescription, indicating the required lens prescription.
CYL (or Cylinder): In Astigmatism, the plus or minus sign in front of the number has a different meaning, the minus sign is used to correct nearsighted astigmatism, the plus sign is used for farsighted astigmatism. You can choose the lens that is closest to, but not higher than, astigmatism according to the value.
AXIS (or AX): the axis of astigmatism is also known as the angle of astigmatism and is measured in 10-degree intervals. Again, choose the closest value of axiality, but try not to fall more than 10 degrees from the axiality, as this will affect the correction effect.
3 major factors affecting the price of myopia and astigmatism contact lenses
After understanding what the labels mentioned above and values represent, the next step is to enter the purchase process, and there are many reasons that affect the price of myopia and astigmatism contact lenses, and the following are the 3 main factors.
The reason for the price of astigmatism contact lenses
- special nature
If there is a need for correction, such as astigmatism, farsightedness, etc., it may be necessary to customize, compared to ordinary contact lenses, the price will be relatively high.
- Wearing cycle
According to the use cycle of contact lenses, they can be broadly divided into daily, biweekly, and monthly, and different replacement cycles will affect the price.
- Hidden eye brand
The last is the brand, whether it is Korean, Japanese, or MIT, many brands launch contact lens products, and the price range of each is not quite the same, so you can compare prices before you buy. If you are a contact lens distributor, then you can come to freshlady, our complete supply chain and professional service team can give you a better price.
Note: Don’t buy products from unknown sources because of the low price. When buying products, it is recommended to check whether the products have some professional license name.